文献类型：期刊文献

英文题名：Enhancing production and purity of 9-OH-AD from phytosterols by balancing metabolic flux of the side-chain degradation and 9-position hydroxylation in Mycobacterium neoaurum

作者：Zhu, Xiaomei[1];Wang, Xiao[1];Zhang, Jian[1];Wang, Xuedong[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2024

卷号：19

期号：1

外文期刊名：BIOTECHNOLOGY JOURNAL

收录：;EI(收录号：20235215267395);WOS:【SCI-EXPANDED(收录号:WOS:001128812400001)】；

基金：This work was supported by the National Natural Science Foundation of China (31570079, 21706072).

语种：英文

外文关键词：9 alpha-hydroxyandrost-4-ene-3,17-dione; Hsd4A; KshA1; metabolic engineering; phytosterols biotransformation

摘要：9 alpha-Hydroxyandroster-4-ene-3,17-dione (9-OH-AD) is a representative steroid drug intermediate that can be prepared by phytosterols (PS) biotransformation with mycobacteria in a resting cell-cyclodextrin system. In this study, over-expression of 17 beta-hydroxysteroid dehydrogenase (Hsd4A) was testified to enhance the side-chain degradation of PS and to reduce the incomplete degradation by-products. Meanwhile, the complete degradation product 4-androstene-3,17-dione (AD) was increased due to the lack of 3-Ketosteroid 9 alpha-Hydroxylase (KshA1) activities. To increase the production and purity of 9-OH-AD, the metabolic pathway of the side-chain degradation of PS and 9-position hydroxylation was modulated by balancing the over-expression of Hsd4A and KshA1 in mycobacteria and reducing the bioconversion rate via lowering the ratio of PS and cyclodextrin. The production and purity of 9-OH-AD in broth were improved from 22.18 g L-1 and 77.13% to 28.27 g L-1 and 87.84%, with a molar yield of 78.32%.